When exposed to environmental conditions of ultraviolet light (UV), extreme heat or cold, rapid temperature change, or moisture in the form of humidity, rain, ice and snow, the mechanical stability of useful articles is needed. A substantial need is seen for an article that has mechanical strength and flexibility, moisture resistance, minimal changes when exposed to changes in temperature, UV and can be easily manufactured.
Thermoplastic composite and extrusion formed structural members and related processes are known for use in useful articles such as transportation vehicles or constituent parts of a building envelope. For example, such members have been commonly used in automotive trunk, door and window seals, exterior siding and window and door assemblies. Such assemblies can be used in commercial or residential architecture or in refrigeration/freezer applications, etc. However, some thermoplastic composite structural members are relatively costly to produce, have deficiencies with regard to structural and/or thermal performance, and are generally formed from non-biologically derived materials. Accordingly, improvements are desired.
Systems are known for separating two or more panes of glass in order to construct an insulated glass assembly. Early constructions, for example those detailed in U.S. Pat. Nos. 4,335,166 and 4,909,874, focused on metal spacer elements to provide structural rigidity and compression resistance to the glass edge, while restricting gas transfer through the exterior perimeter of the spacer material. These constructions suffer from poor insulating capability of the spacer system, resulting in undue heat loss through the system and subsequent cold-weather condensation at the edge of the interior glass pane. In addition, these constructions provide insufficient elastic deformation under compressive loads, resulting in high glass stress and breakage in these conditions. Later art was focused on U-shaped, roll-formed metal spacer constructions that provide adequate elastic deformation, under compressive loads. This art is described in U.S. Pat. Nos. 4,530,195; 5,094,055; 5,177,916; 5,255,481; and 5,361,476. While this art results in reduced glass breakage, the heat loss and condensation issues remain. Still later art focused on replacing much of the metal materials in the spacer system with polymeric materials. Such art is taught in U.S. Pat. Nos. 4,113,905; 4,564,540; 5,443,871; 5,485,710; 5,491,953; 5,658,645; 6,311,455; 6,686,002; and 7,270,859. While these display superior insulating properties, many of these materials contain constituents that vaporize with time and collect as a ‘fog’ on the interior surface on one or more of the panes of the insulated glass. Other systems combine polymeric and metal elements in such a way that the glass periphery is contacted with a hard metal edge. This results in microscopic damage to the glass edge and eventual glass breakage, resulting from this microscopic damage. All of the systems that provide improved insulating capabilities to the spacer by incorporating polymeric constituents as a replacement of metals, result in increased cost due to the higher cost of polymeric materials compared to an equivalent metal component.
Although the art contains many concepts for creating useful assemblies, many configurations fail to provide superior insulating properties, sufficient compression resistance; elastic deformation to prevent stress resistance to microscopic damage in an edge upon handling and exposure; resistance to fogging of the insulated glass.
Systems are also known for residential and commercial construction siding, which is the cladding or outer covering of a structure, meant to protect it from the effects of wind, water and sunlight. The traditional siding material is steel, aluminum, PVC, wood clapboard or beveled siding. Wood members, thin at the top and thick at the bottom, are overlapped in rows or courses. This concept for siding has been used for centuries, but suffers from the problem that the wood members require regular painting or treatment with toxic solutions to prevent fungal decay. They are also prone to attack by insects like carpenter ants or termites.
Metal siding members became popular during the first half of the twentieth century. Steel clapboard siding was patented in 1903 by Sears Roebuck & Company. Later, aluminum became a popular material for this style of siding. The members were designed to be applied as a cladding over the top of existing wood siding in order to avoid the repeated painting and treating processes cited earlier. Metal siding members, however, suffer from problems of corrosion, especially in coastal regions. Metal siding at the material thicknesses commonly used can be dented by hailstorms. In addition, metal siding suffers from the fact that the materials of construction have a finite abundance at the earth's surface and thus, once depleted, are not renewable.
Poly vinyl chloride (PVC) or vinyl siding was introduced in the late 1950's. Its design was essentially a one-for-one replacement to aluminum siding. Because of this, the many adjoining components (outside corner trim, inside corner trim, soffit, etc.) could still be used, enabling easier adoption and scale-up of the product. Today, vinyl is the most commonly used residential exterior cladding in the U.S. Recent siding products made from fiberglass-reinforced cement or fiberglass reinforced polymer have been developed.